I'm excited for the game because it's another game set in the Batman universe, but my main concern is a potential lack of depth in the gameplay since you can play as one of any five characters. With the Arkham games, you got to upgrade Batman and learned his moveset throughout the game. I just hope they don't tone down the depth of combat to allow you to more easily switch through five different playstyles, if that's how the game is designed.
Obviously this game is a ways from coming out, but I figured I'd throw that out there just in case. I'll probably end up getting this game anyway because I love Batman and the Court of Owls storyline was really good, but if they make the gameplay both different and deep for each character, I'll be super happy.